Previous: Cicadas: The Loudest Bugs in the World! | Biology for Kids | SciShow Kids
Next: Fun Summer Science! | A SciShow Kids Compilation



View count:324,971
Last sync:2024-07-13 20:45


Citation formatting is not guaranteed to be accurate.
MLA Full: "Why Are You Left or Right Handed? | Biology for Kids | SciShow Kids." YouTube, uploaded by SciShow Kids, 22 May 2018,
MLA Inline: (SciShow Kids, 2018)
APA Full: SciShow Kids. (2018, May 22). Why Are You Left or Right Handed? | Biology for Kids | SciShow Kids [Video]. YouTube.
APA Inline: (SciShow Kids, 2018)
Chicago Full: SciShow Kids, "Why Are You Left or Right Handed? | Biology for Kids | SciShow Kids.", May 22, 2018, YouTube, 04:21,
Have you ever tried to write or color with both hands at the same time? It seems like it would save a ton of time, right? But for most people, one of their hands is way better at drawing or writing than the other!
Love SciShow Kids and want to help support it? Become a patron on Patreon:
Looking for SciShow elsewhere on the internet?


Squeaks, that is some beautiful art. Look at all those colors you used!

I’m trying to draw a flower garden, and I’ll need to use lots of different colors to do it. I’ll need to use one color at a time, like this. Hmmm … I think this is going to take a while. [Squeaks squeaks].

Oh, you're right! It might go faster if I colored with both hands at the same time. Let’s try it.

I don’t think this is going very well, Squeaks! My right hand is much better at drawing than my left hand. Even just holding the crayon in my left hand is uncomfortable.

So it was a good idea, Squeaks, but I don’t think it’s going to work for me. It’s hard for me to color with my left hand because I’m right-handed — I’m a righty. Most people have one hand that’s better at doing things like writing, drawing, and picking things up.

We call this their handedness. Since I’m right-handed, when I go to pick up a crayon, I naturally want to use my right hand. When I use my left hand, I’m kind of clumsy, and I can’t control it as well as I want to.

Most people are right-handed like me, but about one in every ten people is left-handed — a lefty. Someone who’s left-handed might throw a baseball or use a paintbrush with their left hand, instead of their right. There are even a few rare people who can use both hands really well!

These people are ambidextrous, which just means they’re skilled with both hands. Only about one in every 100 people is ambidextrous, so it’s pretty special. [Squeaks squeaks]. That’s a good question, Squeaks!

He wants to know why most people are righties. Well, scientists still aren’t sure, although they do have a few ideas. One idea is that it has a lot to do with our brains.

Your brain controls everything your body does, and different parts of your brain control different parts of your body. In general, the right side of your brain controls the left side of your body, and the left side of your brain controls the right side of your body. [Squeaks squeaks]. Yeah, it is weird that each side of your brain controls the opposite side of your body!

But that’s just how we’re wired. Earlier, we talked about how most people are right-handed. So which side of the brain would be in charge of moving their right hand? [Squeaks squeaks].

You got it! The left side of your brain controls your right hand. But that’s not all the left side of your brain does.

It’s also in charge of helping you talk. When you talk, you’re making small, careful movements just like when you write or color. You’re just moving your mouth and tongue instead of moving your hand.

So scientists think that it’s easier for the left side of the brain to just be in charge of both talking and those harder small movements like writing, which is why so many people are right-handed. But people who are left-handed or ambidextrous are just as good at using their hands as right-handed people are! Their brains are just organized in a way that might not be as simple.

Another idea is that which hand you use more comes from your parents. Lots of things about people can come from their parents — what they look like, the color of their eyes, how tall they are … you name it! Well, which hand you use might be another one of those things.

Scientists still aren’t sure how exactly this connection works, but if lots of people in your family are left-handed, you’re more likely to be a lefty, too — although you could still be a righty! So most people might be right-handed because it’s easier for one side of your brain to control both talking and writing, and which hand you use might come from your parents. But there’s still a lot we don’t know about how our brains work! [Squeaks squeaks].

I’m not sure when scientists will figure out everything about handedness. We’ll have to keep researching, and see what we can all find out together. If you want to do some research yourself, you can try testing the handedness of your family by having everyone write with their left and right hands.

Are there more left-handed or right-handed people in your family? Is anyone ambidextrous? Squeaks and I will do some more research, too, by finishing up our artwork.

We’d love to hear about your research results! If you’d like to share with us, have a grown-up help you to leave a comment below, or send us an email at We’ll see you next time, here at the Fort! ♪.